﻿using UnityEngine;
using System.Collections;

namespace Assets.Utils
{
    public class FlyCamera : MonoBehaviour
    {

        /*
        Writen by Windexglow 11-13-10.  Use it, edit it, steal it I don't care.  
        Converted to C# 27-02-13 - no credit wanted.
        Simple flycam I made, since I couldn't find any others made public.  
        Made simple to use (drag and drop, done) for regular keyboard layout  
        wasd : basic movement
        shift : Makes camera accelerate
        space : Moves camera on X and Z axis only.  So camera doesn't gain any height*/


        public float mainSpeed = 100.0f; //regular speed
        public float shiftAdd = 250.0f; //multiplied by how long shift is held.  Basically running
        public float maxShift = 1000.0f; //Maximum speed when holdin gshift
        public float camSens = 0.25f; //How sensitive it with mouse
        public bool rotateOnlyIfMousedown = true;
        public bool movementStaysFlat = true;

        private Vector3 lastMouse = new Vector3(255, 255, 255); //kind of in the middle of the screen, rather than at the top (play)
        private float totalRun = 1.0f;
        
        void Update()
        {

            if (Input.GetMouseButtonDown(1))
            {
                lastMouse = Input.mousePosition; // $CTK reset when we begin
            }

            if (!rotateOnlyIfMousedown ||
                (rotateOnlyIfMousedown && Input.GetMouseButton(1)))
            {
                lastMouse = Input.mousePosition - lastMouse;
                lastMouse = new Vector3(-lastMouse.y * camSens, lastMouse.x * camSens, 0);
                lastMouse = new Vector3(transform.eulerAngles.x + lastMouse.x, transform.eulerAngles.y + lastMouse.y, 0);
                transform.eulerAngles = lastMouse;
                lastMouse = Input.mousePosition;
                //Mouse  camera angle done.  
            }

            //Keyboard commands
            Vector3 p = GetBaseInput();
            if (Input.GetKey(KeyCode.LeftShift))
            {
                totalRun += Time.deltaTime;
                p = p * totalRun * shiftAdd;
                p.x = Mathf.Clamp(p.x, -maxShift, maxShift);
                p.y = Mathf.Clamp(p.y, -maxShift, maxShift);
                p.z = Mathf.Clamp(p.z, -maxShift, maxShift);
            }
            else
            {
                totalRun = Mathf.Clamp(totalRun * 0.5f, 1f, 1000f);
                p = p * mainSpeed;
            }

            p = p * Time.deltaTime;
            Vector3 newPosition = transform.position;
            if (Input.GetKey(KeyCode.Space)
                || (movementStaysFlat && !(rotateOnlyIfMousedown && Input.GetMouseButton(1))))
            { //If player wants to move on X and Z axis only
                transform.Translate(p);
                newPosition.x = transform.position.x;
                newPosition.z = transform.position.z;
                transform.position = newPosition;
            }
            else
            {
                transform.Translate(p);
            }

        }

        private Vector3 GetBaseInput()
        { //returns the basic values, if it's 0 than it's not active.
            Vector3 p_Velocity = new Vector3();
            if (Input.GetKey(KeyCode.W))
            {
                p_Velocity += new Vector3(0, 0, 1);
            }
            if (Input.GetKey(KeyCode.S))
            {
                p_Velocity += new Vector3(0, 0, -1);
            }
            if (Input.GetKey(KeyCode.A))
            {
                p_Velocity += new Vector3(-1, 0, 0);
            }
            if (Input.GetKey(KeyCode.D))
            {
                p_Velocity += new Vector3(1, 0, 0);
            }
            return p_Velocity;
        }
    }
}